Answer:
There are several ways you could do this. One of the more common ways would be to say something like this:
"He married Sarah Smith in January 1960. He later married Mary Evans in April 1972." If he was divorced or his wife died, you might want to add that in.
You could also say something like "He adored his wives, Sarah and Mary, who bore him 6 children."
It all depends on how much detail you want to put in the obituary.